Centre-aligning apparatus for croissant dough pieces

Abstract: The present invention provides a center-aligning apparatus for fusiform bread dough pieces such as rolled-up croissant dough pieces (1), including an upstream conveyor (2), and a downstream conveyor (3) located below and adjacent the upstream conveyor. Between the two conveyors (2, 3) and adjacent the upstream conveyor, a pair of concave rollers (4, 4') is arranged. The rolled-up dough piece (1) from the upstream conveyor (2) is deposited on the concave rollers (4, 4') as they rotate, which causes the center of the dough piece to be aligned with the central or widest portion of a gap (G) between the rollers. Also, a pair of shutters (5, 5') is mounted below the concave rollers to receive the dough piece from the rollers and to stably deposit the dough piece on the downstream conveyor (3). This apparatus enables the dough piece to advance in alignment with the central line of the downstream conveyor (3).

Description: This invention relates to the art of center-aligning fusiform bread dough pieces, such as rolled-up croissant dough pieces. It has been difficult to align croissant dough pieces with the conveyor or a folding device while the dough pieces are being conveyed, since the central portion of the dough piece is thicker than the remaining portions. The object of this invention is to provide a center-aligning apparatus located in an upstream zone of an apparatus for folding the croissant dough pieces. Conventional croissants are generally bent or curved at their central portions, and to obtain products of such a shape many forming apparatuses have been developed in the past, such as are shown in Netherlands Patent Application No. 8800402 and German Patent Application No. P4039793.9. According to the prior art, it is not easy to bend the croissant dough piece at its center. To do so, a preceding or preliminary operation is required. The present invention provides a center-aligning apparatus for the croissant dough piece in preparation for the bending thereof. The apparatus according to the present invention enables the center of the croissant dough piece to be correctly aligned with the subsequent bending device while the dough is being conveyed on a conveyor. From one aspect, this invention provides a center-aligning apparatus for croissant dough pieces comprising a pair of concave rollers located between an upstream conveyor that conveys rolled-up croissant dough pieces and a downstream conveyor positioned below and downstream of the upstream conveyor, the rollers being rotatable in the same direction as that of the movement of the upstream conveyor, and being provided with a gap between the pair of rollers which is adjustable so that it can be widened or narrowed. From another aspect, the present invention provides center-aligning apparatus for croissant dough pieces comprising a pair of concave rollers located between an upstream conveyor that conveys rolled-up croissant dough pieces and a downstream conveyor positioned below and downstream of the upstream conveyor, the rollers being rotatable in the same direction as that of the movement of the upstream conveyor, the rollers being provided with a gap therebetween. The gap between the rollers may be adjustable. The apparatus may further comprises a pair of planar shutters below and adjacent the pair of concave rollers, and adapted to be opened and closed, the free longitudinal edge of each of the shutters being inclined downwardly and inwardly when the shutters are closed. In one embodiment of the present invention, the apparatus is provided with a sensor adjacent the downstream end of the upstream conveyor to detect the passage of the croissant dough pieces, and the central gap between the concave rollers is adapted to be widened or narrowed in dependence upon the signals from the sensor. Also the planar shutters are adapted to be opened or closed in dependence upon the signals as the sensor detects the passage of the dough pieces. One embodiment of the invention will now be described with reference to the accompanying drawings:- Fig. 1 is an overall plan view of a croissant dough folding machine that includes the center-aligning apparatus for croissant dough pieces embodying the present invention; Fig. 2 is an overall side view of the machine shown in Fig. 1; Fig. 3 is a front sectional view of the center-aligning apparatus embodying the present invention; and Fig. 4 is a partial side view of the apparatus of Fig. 3. The center-aligning apparatus for croissant dough pieces embodying the invention comprises an upstream conveyor 2 to convey rolled-up croissant dough pieces 1, and a downstream conveyor 3 located downstream of and below the upstream conveyor 2. A pair of concave rollers 4, 4' are located adjacent the upstream conveyor 2 and between the upstream conveyor 2 and the downstream conveyor 3. The concave rollers 4, 4' are positioned side by side with their axes positioned horizontally and laterally to the direction of movement of the conveyors. The diameter of each of the rollers 4, 4' is reduced towards its central portion, so that a gap G is formed between the rollers. The concave rollers 4, 4' are fixed to roller shafts 41, and the roller shafts are supported by arms 42, 42', which in turn are supported by intermediate shafts 43,43'. Both the roller shafts 41 and the intermediate shafts 43, 43' are oppositely disposed. Similarly, the rollers 4, 4' are oppositely located, each being fixed to one of the roller shafts 41, 41'. The intermediate shafts 43 have gears 44 and 44', which mesh with each other. The arm 42 is connected to a rod 46 of an air cylinder 45, so that when the air cylinder is operated to pull the arm 42, the other arm 42' is swung by the gears 44, 44' in the opposite direction about the intermediate shaft 43', thereby to widen the gap G between the concave rollers 4, 4'. A pulley 47 is fixed to the end of the roller shaft 41, and the roller shaft 41 of the concave roller and the drive shaft of a motor 48 are connected by belts 31, 32 via a pulley 49 fixed to the intermediate shaft 43. A pair of opposite planar shutters 5, 5' is provided below and adjacent the concave rollers 4, 4'. They are adapted to be opened and closed, and the free longitudinal edge 53 of each of the shutters is inclined downwardly and inwardly when the shutters are closed. An actuator 52 is mounted on a frame about, and coupled to, the swing shaft 51 of one of the shutters 5, 5'. One end of each of the swing shafts 51 is connected to the adjacent end of the other swing shaft by gears (not shown). Thus, when the actuator 52 is actuated, the shutters rotate about the swing shafts 51 to widen the space between the free edges 53. The central portion of the free edge of each shutter is formed with a V-shaped cut-out 54. A pair of freely-rotatable inclined rollers 6 is positioned on the downstream conveyor 3. The downstream ends of the inclined rollers are inclined toward each other, and the inclined rollers 6 and the conveying surface of the downstream conveyor 3 are positioned parallel to each other. Dough-piece holding belts 7 are provided adjacent and downstream of the inclined rollers 6. The dough-piece holding belts 7 consist of two thin endless belts, which are trained in parallel relationship. The speed of the dough-piece holding belts 7 is the same as the conveying speed of the conveyor 3. The dough-piece bending apparatus of the present invention comprises, in addition to the conveyor 3, a dough-piece bending member 8 and a pair of dough-piece bending belts 9. The bending member 8 includes a roller 81 having flanges 82 at each side of it, an air cylinder 83 for lowering the roller 81 toward the conveyor, and an air cylinder 84 for moving the frame that supports the air cylinder 83. in the same direction as that of the movement of the conveyor 3. A photoelectric sensor or tube 85 is provided to sense the passage of the croissant dough piece 1. In this structure, when the roller 81 receives a signal from the photoelectric tube 85, the roller 81 pushes the croissant dough piece 1 in the direction of its movement into the space between the bending belts 9, which are located downstream of the roller 81. The bending belts 9 consist of endless belts 93 each trained around a drive roller 91 and an idler roller 92. The belts 9 are positioned on the conveyor 3 so that they converge in the downstream direction, and they are adapted to swing toward and away from each other. Namely, each of the outer portions of the endless belts 93 that is normally positioned adjacent the longitudinal edge of the conveyor 3 can rotate about the shaft of the drive roller 91, inwardly toward the central line C of the conveyor 3. The function of the apparatus embodying the present invention will now be explained. A croissant dough piece 1 that was rolled up by a conventional rolling-up device is conveyed along the upstream conveyor 2. The croissant dough piece 1 is then delivered from the upstream conveyor to the gap G between the concave rollers 4, 4'. At this point, since the rollers 4, 4' are adjacent each other, this gap G is small. The rollers rotate in the same direction. Thus the dough piece is forced to be rotated so as to move toward the central portion of the rollers. Therefore, even if the central portion of the croissant dough piece 1 is not initially aligned with the central moving line C of the conveyor, the dough piece is rotated so that the central thick portion of the dough piece and the gap G, and in particular the central wide space between the rollers 4, 4', are aligned. Thus the central moving line C of the conveyor and the center of the dough piece 1 are eventually aligned. Thereafter, the gap G between the rollers 4, 4' is widened, causing the croissant dough piece 1 to fall into the shutters 5. The shutters serve to stop the rotation of the croissant dough piece 1 and deposit it onto the downstream conveyor 3. Since the shutters are formed with cut-outs 54, the thick central portion of the dough piece 1 is snugly positioned on the cut-outs 54 when the dough piece falls into the shutters 5. Thus, the dough piece is held in a stable manner in the shutters. Thereafter, the shutters are opened to deposit the croissant dough piece stably on the downstream conveyor 3. Therefore, the dough piece 1, the center of which has been aligned by the concave rollers 4, 4', can be correctly deposited on the downstream conveyor 3, when the rollers and shutters are opened. Namely, the center of the fusiform dough piece can be precisely aligned with the center line C of the downstream conveyor 3. A control unit or panel 22 is provided on a frame (not shown). The control panel has a sequencer, and controls the operational sequence of the concave rollers 4, 4' and the shutters 5, 5', as follows: 1) A sensor 21 senses the passage of the croissant dough piece 1 and transmits the signal to the control panel 22. 2) After a predetermined time interval following sensing of the dough piece 1, the small gap G between the concave rollers 4, 4' is enlarged and shortly thereafter is made smaller again by the signal from the control panel 22. 3) The shutters 5 are opened and soon closed again by the signal from the control panel 22. Since this operational sequence is correctly controlled by a sequencer, etc., the center alignment of the croissant dough piece can be precisely carried out regardless of whether the dough is regularly supplied or not. Although, in this embodiment, the height of the rollers 4, 4' is the same, it need not be the same. For instance, the height of the downstream roller 4' could be made slightly higher than that of the upstream roller 4, depending on the moving speed, or the size, of the dough piece. Thus the height of the rollers can be adjusted as desired. By so adjusting, the dough piece can be prevented from dropping off the rollers when it is rotated. Also, the tapering angle of the concave portion of each roller can be determined depending on the shape or thickness of the dough piece. If the central portion of the croissant dough piece is thick, it is of course preferable to give the rollers a larger tapering angle, so that the gap G can become larger. Similarly, when the central portion is thin, the tapering angle should be lessened. Further, the speed of the rotation of each concave roller is adjusted, based on the elasticity of the dough or on how smoothly the center of the dough piece moves to the center line C of the conveyor. In this embodiment a good result was obtained when the rotational speed of the upstream roller was set at 40m/min and that of the downstream roller 80m/min, respectively. Of course, other speeds may be chosen with good results. The rollers, in this embodiment, are made of polyacetal, and the upstream roller is formed with spiral grooves to help move the dough piece toward the center of the rollers when they are rotated. The dough piece 1 deposited on the downstream conveyor 3 is then received by the inclined rollers 6. Thereafter the dough piece receives further processing in the subsequent operation lines. The processing includes detection of the rolled-up end of the dough piece by a laser sensor to place the dough piece in a predetermined orientation, and further bending it at its center. As explained above, in the present invention the rolled-up croissant dough piece is rotated and aligned with a central or control position by a pair of rotating concave rollers. After the gap between the concave rollers is widened, the dough piece is conveyed downstream along the central line on the conveyor. Also, a pair of shutters, as known from the prior art document FR-A-1208012, is provided below and adjacent the concave rollers. The shutters can open and close with their free edges inclined downwardly and inwardly. Thus, the croissant dough piece can be stably deposited on the downstream conveyor and is carried downstream. Further, since a cut-out is formed in each shutter, the shutters can receive the dough piece in a desired position, causing the dough piece to be precisely deposited on the downstream conveyor. Also, since the operations to widen and narrow the gaps of the concave rollers and the shutters are carried out by the signals from the sensor located adjacent the downstream end of the upstream conveyor, the center aligning operation of the croissant dough piece can be performed regardless of whether the dough pieces are regularly supplied or not. As is clear from the above, even if the conveying direction or the orientation of the dough piece is not fixed, or even if the distance between the adjacent croissant dough pieces is not uniform, the center of the dough pieces can be aligned with the central line on the downstream conveyor. Thus the dough pieces can be conveyed downstream in an orderly manner, enabling them to be correctly processed in subsequent lines. By this invention it has become possible to provide products of higher quality with higher productivity, compared to those produced by the conventional art.

Claims: A center-aligning apparatus for croissant dough pieces,characterised by a pair of concave rollers (4, 4') located between an upstream conveyor (2) that conveys rolled-up croissant dough pieces (1) and a downstream conveyor (3) positioned below and downstream of the upstream conveyor (2), the rollers (4, 4') being provided with a gap (G) therebetween and being rotatable in the same direction as that of the movement of the upstream conveyor (2). An apparatus according to claim 1, wherein the gap (G) between the pair of rollers (4, 4') is adjustable. An apparatus according to claim 1 or 2, further comprising a pair of spaced-apart planar shutters (5, 5') below and adjacent the pair of concave rollers (4, 4') and adapted to be opened and closed, the free longitudinal edge (53) of each of the shutters being inclined downwardly and inwardly when the shutters are closed. An apparatus according to claim 3, wherein the free longitudinal edge (53) of each of the shutters (5, 5') has a cut-out (54) at its central portion. An apparatus according to claim 3 or 4, , wherein a sensor (21) is provided adjacent the downstream end of the upstream conveyor (2) to detect the approaching dough pieces (1) and to send signals so as to open or close the shutters (5, 5'). An apparatus according to any preceding claim, wherein a sensor (21) is provided adjacent the downstream end of the upstream conveyor (2) to detect the passage of the croissant dough pieces (1) on the upstream conveyor, the sensor being adapted to provide signals, and the gap between the concave rollers (4, 4') being widened or narrowed based on the signals from the sensor.

Inventors: KUWAHARA HITOSHI, MORIKAWA MICHIO, UENO SADAO, KUWAHARA, HITOSHI, MORIKAWA, MICHIO, UENO, SADAO, KUWAHARA, HITOSHI, RHEON AUTOMATIC MACH. CO., LTD., MORIKAWA, MICHIO, RHEON AUTOMATIC MACH. CO., LTD., UENO, SADAO, RHEON AUTOMATIC MACH. CO., LTD.
Applicants: RHEON AUTOMATIC MACHINERY CO, RHEON AUTOMATIC MACHINERY CO. LTD.
Application year: 1994
Main classification: A21C3
IPC codes: A21C9, A21C3